cc: Remove cc::Thread and cc::ThreadImpl.

cc/cc.gyp

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 {
   'variables': {
     'chromium_code': 1,
     'cc_source_files': [
       'animation/animation.cc',
       'animation/animation.h',
@@ skipping 25 matching lines @@
       'base/math_util.cc',
       'base/math_util.h',
       'base/region.cc',
       'base/region.h',
       'base/scoped_ptr_algorithm.h',
       'base/scoped_ptr_deque.h',
       'base/scoped_ptr_hash_map.h',
       'base/scoped_ptr_vector.h',
       'base/switches.cc',
       'base/switches.h',
-      'base/thread.h',
-      'base/thread_impl.cc',
-      'base/thread_impl.h',
       'base/tiling_data.cc',
       'base/tiling_data.h',
       'base/util.h',
       'debug/debug_colors.cc',
       'debug/debug_colors.h',
       'debug/debug_rect_history.cc',
       'debug/debug_rect_history.h',
       'debug/devtools_instrumentation.h',
       'debug/fake_web_graphics_context_3d.cc',
       'debug/fake_web_graphics_context_3d.h',
@@ skipping 311 matching lines @@
         'CC_IMPLEMENTATION=1',
       ],
       'sources': [
         '<@(cc_source_files)',
       ],
       # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
       'msvs_disabled_warnings': [ 4267, ],
     },
   ],
 }